Okay. Here is a group shot of your options.
Back left, a one-piece holesaw, good for one-time use. It is hard to get the wood or acrylic out of the saw once the hole has been drilled, but with a nail, you can poke it out.
Back right, a hole saw kit from Harbor Freight (or Home Depot) with many sizes.
Front, Blumol drill bits, along with the drill shank.
I prefer the Blumol saws (at Home Depot) because they don't heat up and melt the acrylic, and it is easier to get the acrylic out of the saw once done. They cost more. The drill bit section and the saw (white section) will run you about $20. As you can see, I have three bits, for 1", 1.5", and 2" bulkheads. The bit for a 1.5" bulkhead will drill a 2 3/8" hole in the acrylic.
Here's a picture of the drill bit section, which has a knurled collar that is twisted to raise locking pins.
The white section threads onto the drill bit, and then the collar is twisted to engage the locking pins, like this:
The next best option will cost you $5 to $12, and you'll get an entire kit, but make sure it contains the size you need. This bit will get quite hot and the acrylic will melt a little.
By loosening this nut, you can exchange various hole saws depending on the task at hand.
And finally, the one-piece bit. I rarely use these unless I'm stuck and can't find another. It won't cost much, under $5 I think. It definitely will get hot and melt the acrylic.
Driling the hole doesn't take long at all. The center drill bit will keep it from wandering. Press down gently while drilling, and within 45 seconds you'll have a hole. Once the hole has been drilled (I use a cordless DeWalt drill), you'll need to remove any burrs; a chisel will do this job adequately.. Sand it lightly, and make sure the inside and outside of the hole are smooth to the touch. Done!
